B3

Question 1

what reproduction is meiosis in

Answer 1

sexual

Question 2

is meisosis offspring genitcally different

Answer 2

yes

Question 3

gametes

Answer 3

reproductive cells

Question 4

gametes contain how kany chromosomes

Answer 4

haploid
half the amount of

Question 5

zygote

Answer 5

fertilised egg

Question 6

how kany chromosnes do zygote have

Answer 6

full amount
diploid

Question 7

division 1

Answer 7

-duplicates dna so enough chrimo when it divides
-chromosomes line up in pairs (one from mum one from dad)ik centre cell
-pairs pulled apart so new cell only hv copy of one some mum some fad
-mixture of genes creates genetic variation

Question 8

division 2

Answer 8

-line up again in centre n arms (chromatids) r pulled apart
-4 haploid dsughter cells ehich r gametes
-each gamete has single set of chromosomes all gametes r geneticslly different

Question 9

asexual pros

Answer 9

-lots offsping quick bc reproductive cycle is vv fast
-only one parent needed,dont hv to wait for mate

Question 10

asexual cons

Answer 10

-no genteic variation
-if environment changes n comditions r bad whole population cld be affected

Question 11

sexual pros

Answer 11

-genetic variation
-which can lead fo natural selection n evolution

Question 12

sexual cons

Answer 12

-more time and energy to produce fewer offspring
-2 parents needed

Question 13

whay is dna made up of

Answer 13

nucleotides

Question 14

what does each nucleotide consist of

Answer 14

sugar
phosphate group
one base

Question 15

what is the sugar a phosphate groups for

Answer 15

form a backbone to dna strands

Question 16

the bases

Answer 16

A
I
C
G

Question 17

complementary based pairinh

Answer 17

A paired w T
C paired w G

Question 18

whys complementary bade pairs held theyhet by

Answer 18

weak hudrogen bonds

Question 19

what does all of organisms dna make up

Answer 19

genome

Question 20

extract dna from fuit cells

Answer 20

-fruit in beaker
-containing detergent and salt
filture mixture to get frogh and big insoluble bits of cell oht
-add ice cold alchol to filtured mixture
-dna eill start to come out as a stringy white precipitate

Question 21

what dies detergent to in extract fna oratical

Answer 21

break down cell membranes to release dna

Question 22

what does saly do in extract dna practical

Answer 22

make dna stick togethrr

Question 23

what can dna control

Answer 23

production of protiens (protien synthesis) in a cell

Question 24

each different protien has

Answer 24

its own bumber and order of amino acids

Question 25

why do amino acid chains fold up

Answer 25

to give wach protien a different specific shape

Question 26

base triplet

Answer 26

the sequence of 3 bases in the gene rhat amino acid is coded for

Question 27

each gene contains a different sequence id bases why

Answer 27

it allowe it to code for a particular protien

Question 28

regions of dna that are non coding

Answer 28

they dont code dor any amino acid

Question 29

mutation

Answer 29

rare random change to organisms dna base sequence can be inhereted

Question 30

what 2 stages are proteins made in

Answer 30

transcription translation

Question 31

messages in cell protiensynthesis transcription

Answer 31

-protien made in ribosomes -dna in nuclues but cant move out so cell needs to get info from dna to ribosome in cytoplasm -done by messenger rna

Question 32

rna polymerase

Answer 32

enzyme invokved in joining rna nucleotids to maie mrna

Question 33

transcription

Answer 33

-rna polymerase binds to region of non codininh dna iffrint of a gene -2 dna strands unzip and rna plumerase moves along one of strands of dna -uses coding dna in gene as a template to make mrna. -base paring between dna and rna enzures that mrna is complementary to the gene -once made mrna molecules moces oht of molecules and joins w ribosomes

Question 34

translation

Answer 34

-amino acids brought to ribosome by transer rna -order which amino wcids bought in katches order of base triplets in mrna -part of trnas structure is anitcodon —codon and anticoden pair so amino acids are brought to ribosomes in right order -amino wcids joint tgther by ribosomes -makes polypeptide(protien)

Question 35

xx

Answer 35

female

Question 36

xy

Answer 36

male

Question 37

what chromosome is smallrr

Answer 37

Y and it carries fewer genes. so most genes are carried on x

Question 38

what are sex linked genetic disorders caused by

Answer 38

faulty alleles located on sex chromosomes

Question 39

colour blindness

Answer 39

faulty allele carried on x

Question 40

xn

Answer 40

x chromosome n faulty allele

Question 41

what can genetic variation be caused by

Answer 41

new alleles arising through mutations environment

Question 42

phenotype

Answer 42

characterists organsim displays

Question 43

mutatioms

Answer 43

changes to base sequence of dna can have small effect in phenotype

Question 44

human genome project

Answer 44

find every single human gene tryna figure out what they di now theyve been found

Question 45

prediction and prevent of diseases hjp

Answer 45

if doctord knew what genes predisosed ppl to what disease we cld all get specific tailored advice on best lifestyle to avoid our problems

Question 46

testing and treatement for inhereted disords hjp

Answer 46

sceinetinia now can identify the genes and alleles that are supsected to cayse inhereted disorders

Question 47

new ajd better medicines hjp

Answer 47

design drugs tailored to specific gentic variation

Question 48

cons hjp

Answer 48

increased stress-sm1 knew ab disease they cld get geneism-not wnat to hv children dicrimination by emoloyers or insures